Apparatus for preparing fuel for combustion



March 21, 1939. w. TSCHUDY z-:T Al. 2,151,060

' APPARATUS FOR PREPARING FUEL FOR OMBUSTIN Filed July 51, 1955 z'sheets-sheet 1 if 527 a @THM lTTUEA/'Eyi March 2l, 1939. W- TSCHUDY ET AL I 2,151,060

APPARATUS FOR PREPARING FUEL FOR COMBUSTION Filed July 3l, 1933 2 Sheets-Sheet 2 W 65 Z v 23 NVENTURS WT 5B1- mur TIL-Ig@ TTURNEYS.

. 50 system having the above mentioned characterbranch in turn may be branched, the various 50 Patented Mor.21,1939 t e y 2,151,060

UNITED STATES PATENT'OFFICEv APPARATUS FOR PREPARING FUEL FOB COMBUSTION William 'luscliudy and Thomas W. Halliday, Los Angeles, Calif., assignors of one-third to Barry Dibble, Redlands', Calif.

Application July 31, 1933, Serial No. 682,994

7 Claims. (Cl. 158-53) This invention relates to improvements in an to use in conjunction with the improved system. apparatus for preparing fuel for combustion. It with the foregoing and other objects in view concerns, particularly, an apparatus which has which will 'be made manifest in the following been primarily designed for heating orchards, detailed description l'and specifically pointed out groves, and other outdoor vegetation so as to in the appended claims, reference is had to the 5 Prevent damage from fr0Si1 The present apaccompanying drawings for an illustrative em- Lparatus may also be used as a complete heating bodiment of the invention wherein:

system for a small farm in that it can be used Fig. 1 is a schematic view illustrating the preto heat the orchards, groves, and other vegetaferred construction embodying the invention.

tion and also supply fuel to a farmhouse for Fig. 2 is a vertical section taken substantially 10 domestic purposes. upon the line 2-2 upon Fig. 1.

An object of the invention is to provide an ap- Fig. 3 is a vertical section illustrating` in detail paratus which utilizes hydrocarbon gases of the an arrangement of parts which may be employed butano-propane series or equivalent fuels. These to effect an automatic operation of the system.

fuels will naturally volatilize quite readily under Fig. 4 is a schematic view illustrating a modi- 15 ordinary atmospheric conditions of temperature fled apparatus embodying the invention. and pressure. The gases of the butano-propane Fig-5 is a view in vertical section through one series may be rendered liquid and handled as form of orchard heater which may be employed in such by imposing a pressure. They are colorless conjunction with the improved system.

and highly volatile and are clean to handle. Fig. 6 is a vertical section through an alterna- 20 They produce a flame which, under proper contive form of orchard heater which may be emditions of combustion, is smokeless, generating a ployed. p

high heat. Referring to the accompanying drawings where- Irl keeping the gases 0f Phe butano-propane in similar reference characters designate Simlseries in a storage tank and in liquid form, it is lar parts throughout and particularly to Figs. 1, necessary to convert the liquid into a gas or vapor 2, and 3, the improved apparatus in its preferred for combustion. This conversion may take place form consists of a suitable storage tank I0, prefin accordance with the present system either in erably mounted over a concrete re box I I, at one the storage tank itself or at or near the burner end of which there maybe aflue I2. This storage or burners, or at any intermediate point between tank is preferably supplied with a liquid level 30 the storage tank and the burner. When the presgauge I3 or any other device for indic.ting the sure under which the eases are kept is relieved. quantity of liquid fuel in the storage tank. The the release of the pressure produces a 'quick tank is provided with a filling valve I4 and a disvolatilization of the liquid. This volatilization charge valve I5. The outlet from the tank is has a cooling effect upon the remaining liquid indicated by a pipe I 6 which may be provided 35 with the result that the remaining liquid shortly withapressure gauge I'I indicating the pressure of has its temperature greatly reduced. With the the gaseous fuel which collects in the top of the lowered temperature the tendency of the liquid tank. Pipe I6 may lead' to any lsuitable burner gases to volatilize under the reduced pressure beor set of burners. It is shown on the drawings 40 comes retarded so that eventually a point of as being branched, one branch indicated at I 'I 40 equilibrium is reached where the volatilization of having a valve I8 and a pressure regulator I9. the liquid is too slow to supply the demand created This branch may lead to a suitable burner such by the burner or burners. as at 20, such as a stove burner in a farmhouse Specifically, an object of the present invention used for domestic purposes. In such a case the is to provide a system for counteracting the pressure regulator I9 is so adjusted as to reduce 4 tendency of the volatilizing to so reduce theftemthe pressure of the gas to the desired degree for perature of the remaining liquid that the 'demand stove burner purposes. made by the burner or burners cannot be supplied. The other branch of pipe I6 is provided with a Another object of the invention is to provide a valve 2l and a pressure regulator 22. 'I'his istics which automatically serve to maintain a branches having valves 23 and supplying suitsupply of gas which has been converted from the able orchard heaters, indicated at 24, which may liquid at the desired pressure. be suitably located throughout a grove, such as Another object of the invention is to provide an orange grove. an `improved form of orchard heater designed 'A third branch oi pipe I 6 indicated at 25 leads 65 to a burner 26 in the end of the fire box II, which is opposite the flue or stack I2. Branch 25 is controlled by means oi a thermopressurestat assembly 21' including a valve indicated at 21 (see Fig. 3), and in the preferred form of construction this valve is automatically regulated.

Liquid fuel in the form of liquefied butane gas or a mixture of butane-propane and similar hydrocarbons is maintained under pressure considerably above atmospheric in tank I0. In opening valve I8 or valves 2| and 23 to supply gaseous fuel from the top of tank Il) to a burner, the pressure within the tank is reduced. This reduction of pressure enables the butane to volatilize or vaporize within the tank. Depending: upon the demand created by supplying the various burners which may have been turned on, the liquid fuel has its temperature reduced by the volatilization. The greater the demand and the greater pressure reduction in tank I0, the greater will be the volatilization and reduction of temperature of the liquid. If this situation is permitted to continue, the temperature of the liquid. is so greatly reduced that it willno longer vaporize with sufficient rapidity -to supply the demand unless precautionary measures are taken. To counteract this cooling of the liquid by its vaporization, more fuel is supplied burner 26.

It receives some of the vaporlzed fuel and burns it in the fire box beneath the tank, thus keeping the liquid suillciently warm to cause it to vaporize with the rapidity required by the open burners.

While the rate at which heat is supplied to the tank in this manner may be manually controlled, we prefer to have it automatically controlled as by a thermopressurestat assembly 21.

To this end a pressure pipe 28 leads from they top of tank I0 to the interior of a bellows 29 (see Fig. 3). This bellows has one end connected to a lever 30 pivoted at 30' to a xed structure which opens and closes valve 21. pressure in the top of tank III and which is conveyed by pipe 28 to the interior of bellows 29 is greatly reduced, the bellows may contract with the result that valve 21 pens,lsupplying additional fuel to burner 26 and thus increasing the quantity of heat supplied to tank III to cause the liquid fuel therein to be maintained at the proper temperature to vaporize with suilicient rapidity to supply the demand and to maintain the required pressure in pipe I6 and its various branches. When, however, pressure within tank III increases, which may be due to an excessive burning in the re box or a shutting of valve I8 or 2|, or some Aof valves 23, the increased pressure expands bellows 29, thus tending to close valve 21 and reducing the vquantity of heat supplied to tank I 0. In this way the quantity of heat supplied to tank I0 ls automatically made inversely proportional to the pressure therein and a reduction of pressure causes additional heat to be supplied whereas an increase of pressure reduces the heat supplied.

A simultaneous thermostatic control may also be utilized and for this purpose' there is illustrated on Fig. 3 a thermostat consisting of container 3l containing a heat expansive fluid operable on a diaphragm 32. This diaphragm is connected by means of a rod 33 to a wedge 34 slidable between a counterpart wedge 35 and an adjusting screw 36. When the temperature within the orange grove is lowered the contraction of the fluid within container 3| causes wedge 34 to be drawn toward the right with the result that the bellows 29may bodily move upward irre- When the spective of the pressure conditions. The upward movement of the bellows produced by the shifting of the wedge and irrespective of pressure conditions is sufcient to open valve 21 to supply additional fuel to burner 26. It will be understood that when temperature in the grove goes down it becomes desirable to supply additional fuel .to the heaters 24 therein. I The thermostat in this way increases the -heat supplied to tank I0 and thus increases the rate of vaporization of the liquid to supply the demand for this additional fuel in the grove. Likewise, a rise in temperature in the grove causes the thermostat to shift wedge 34 toward the left, thus tending to close valve 21 irrespective of the pressure conditions. It will be. understood that where the thermostat^is used in conjunction with the bellowsthat both temperature and pressure variations automatically control valve 21.

The bellows 29 is always urged into uppermost -position either by the weight of valve 21 or a counterweight applied to the left hand end of lever 30 or it may be urged into uppermost position by springs (not shown).

It is not essential that the automatic temperature 'and pressure control for valve 21 be em-i'v ployed. An inferior construction may be provided by using merely a hand operated valve in place of valve 21, which can be roughly adjusted to suit conditions. It is also not essential that the automatic control be located immediately in the neighborhood of the tank. A remote control may be utilized if desired.

The types of heaters which may be used with the improved system may be any conventional heater designed to burn .gaseous fuel. We have illustrated two types of heaters which may be employed, one being designed'to heat the surrounding atmosphere principally by radiation. This type of heater is illustrated in=Fig. 5, consisting of a truste-conical sheet metal base 31 having air inlets 38. The pipe supplying the fuel is indicated at 39 and extends into the base, having .an upwardly directed nozzle 40 which discharges into the throat of a venturi 4I. This venturi is supported on the base by means of lugs 42 and has burner perforations 43. A stack 44 is mounted on the base over the venturi and has apertures 45 near its top providing outlets for the products of combustion. On top of the stack there is a cover 46 suspending a reflector 41 of inverted conical shape. The gaseous fuel discharged through nozzle 40 and through the throat of venturi creates an induction of air which mixes with the fuel and the mixture burns issuing through apertures 43 in the stack. The products of combustion issue through apertures 45 and to a certain limited extent heat the air by convection. Much of the heat generated, however, radiates to stack 4 4 and, in turn, is radiated therefrom through the surrounding air toward adjacent vegetation.' The reflector 41 receives considerable heaty which rises Within the stack and reflects this heat back against the walls of the stack which, in turn, radiates it.

In Fig. 6 there is illustrated a type of heater relied upon to-heat the surrounding air principally by convection. This type of heater is designed to warm a large volume of air a few de'- grees in temperature. This heater consists of a. base 58 having air inlet apertures 5I, and the supply pipe 52 extends into the base having an upwardly directed nozzle 53 discharging into the throat of a venturi 54 having burner apertures or perforations 55. Thereover there is posi- Y trols the flow of liquid instead of gases.

tioned a radiator 56 surrounded by a mantle 51. The space between the radiator and the mantle is open at the top and bottom except for supporting brackets or spiders. The top of the radiator is covered by a cover plate 58, immediately beneath which there are apertures 59 for the products of combustionto escape. The fuel in this type of heater Yonburning heats the .radiatpr 56 principally by radiation and some convection. The mantle 51 receives considerable heat from the radiator byradiation, and air on passing upwardly between the radiator and mantle will be heated by these parts. The air will freely circulate therethrough by convection and will become warmed. In this type of construction the intention is to heat a large volume of air but to heat it only a few degrees, this being suilicient to prevent frost or freezing in adjacent vegetation.

On Fig. 4 there is illustrated a modied form of construction for handling and preparing the fuel. In this type of construction, the storage tank 66 is supported on a fire box 6I having a stack 62. 63 designates a filling valve and 64 a discharge valve- A gauge glass is indicated at 65 for indicating the liquid contents of the tank, Liqueed butane or similar fuel of the butanepropane series is maintained in the tank and is discharged through an outlet 66. In this form of construction the fuel passing through pipe 66 is in liquid form and is not converted into a gas until it reaches' the locality of the burner. One type of burner is illustrated on the figure indicated at 61. In this burner it will be noted that a portion of the pipe is bent over the locality of the flame so as to receive heat. Consequently, although liquid butane is fed through pipe 66 directly to the burner and reduction in pressure at the burner enables the butane to vaporize, cooling the liquid in the pipe, the supplying of heat from Athe burner itself to the liquid counteracts the tendency of the vaporization created by the reduction in pressure to reduce the temperature of the liquid to such an extent that it would otherwise shortly stop the flame at the burner. Consequently, in this type of construction fuel will continue to burn freely at the desited rate. As a means for preserving pressure in the tank, a burner 68 similar to that shown at 61 is located within the re box and receives fuel through a branch pipe 69 which may be provided with a thermopressurestat valve assembly similar to an automatic valve arrangement such as is illustrated in Fig. 3. If desired, a pressure regulator 1| may be located in line 66, regulating the pressure at which fuel is delivered to the burners which may be lower than that which it is desired tomaintain normally in tank 66. The vapor -pressure pipe 28 leads from the top of the reservoir to the assembly 21 which includes a Ivalve similar to the valve 21 except that it con- It is desirable to employ a hand operated valve and to regulate the flow of'the'liquid fuel to the heating burners as well as to the reservoir burner in addition to the pressure regulator 1I.

From the above described constructions it will be appreciated that a novel system is provided enabling lthe use of hydrocarbons such as butane or other gases of the butane-propane series. The apparatus is such as to enable the butane to be stored in liquid form. thus reducing the storage space required and the continued vaporization of the fuel and the maintenance of the desired pressure without involving a reduction of temperature of the liquid fuel to such an extent that the vaporization will not supply the demand made by the burners.

In Fig. 3 we illustrate in a somewhat diagrammatic manner an instrument which for sake of terminology may be designated as a thermopressure-stat. 'I'his is an important instrument in regulating the flow of gas to the burner 26 of Fig. 1 or the flow of liquid fuel to the burner 68 of Fig. 4. It will be noted by the prior description in the specification that the control' of valve 21 in fuel pipe 25 is by the combined action of the bellows, which is the pressure part of the instrument, and the actuation of the diaphragm 32 which is the thermostat part of the instrument. The control of the supply of fuel is not entirely by the external temperature developing a simple thermostat control nor is it solely by the pressure in the tank as indicated by the bellows 29 but the combination of both of these devices into a single instrument give a control of the fuel to the burners underneath the tank to properly supply the fuel to the burners exposed to external atmosphere as for instance in the orchard heater burners.

Various changes may be made in the details of construction without departing from the'spirit or scope of the invention as defined by the ap- .pended claims.

We claim:

l. An apparatus for preparing and using a fuel of the butane-propane type or series, comprising in combination a closed reservoir in which the fuel is maintained in liquid form together with posed to the atmosphere for heating, a conduit from the reservoir to the said burner through which fuel is supplied by the vapor pressure in the reservoir, means to heat the reservoir to replace the heat lost from the liquid due to vaporization of such liquid in the reservoir and a means to regulate the reservoir heater governed by the vapor pressure in the reservoir, together with the atmospheric temperature approximate to the burner, whereby as the vapor pressure decreases, the heat to the reservoir heater is increased and as the atmospheric temperature decreases, the heat of the reservoir heater increases, and vice versa.

2. An apparatus as claimed in claim 1, the o reservoir heater comprising a reservoir burner, a fuel .connection means from the reservoir to said reservoir burner whereby fuel is forced from the reservoir to the reservoir burner by the vapor pressure in the reservoir and the regulating means comprises a valve in the reservoir burner supply with means to actuate said valve by contraction or expansion of vapors under the vapor pressure of the reservoir and a thermostat exposed to the atmosphere approximate to the atmospheric burner.

3. An apparatus for preparing and using a liquid fuel which volatilizes under ordinary atmospheric conditions for combustion, comprising in combination aclosed storage reservoir for containing the liquid fuel ata super-atmospheric pressure, a heater burner, a conduit for conveying fuel from the reservoir, to the heaterburner, a heater for the reservoir, the heater for the reservoir comprising a reservoir burner for heating such reservoir with a fuel connection means from the reservoir to said reservoir burner for fuel forced to the reservoir burner by the vapor pressure in the reservoir and a means to regulate the ow of the fuel to the reservoir burner governed Athe vaporized fuel, an atmospheric burner exf by the vapor pressure in the reservoir and the atmospheric temperature approximate to the heater burner whereby as the vapor pressure in the reservoir decreases, the reservoir burner fuel is increased and as the atmospheric temperature decreases, the reservoir burner fuel increases.

4. An `apparatus for preparing and usingl a fuel of the butane-propane type or series comprising in combination a closed reservoir in which the fuel is maintained in liquid form, together with vaporized fuel at the top of the reservoir, a heating burner, a conduit from the upper part of the reservoir to the burner through which fuel gas is supplied by the vapor pressure in the reservoir, a reservoir burner, a gas connection from the reservoir to said reservoir burner with a control vvalve therein and means to automatically operate said valve whereby as heat is extracted from the liquid fuel in the reservoir by vaporization in the reservoir due to thesupply of fuel to the heating burner, the valve is operated to give an increasedygas supply to the reservoir burner to thereby add heat for vaporization of the liquid fuel in the reservoir and hence increase the gas supplied to the heating burner and vice versa, the means to automatically operate the valve including a thermostat exposed to the atmosphere approximate to the heating burner whereby as the atmospheric temperature decreases, the opening of the valve is increased and vice versa.

5. An apparatus for preparing and using a fuel of the butane-propane type or series comprising in combination a closed reservoir in which the fuel is maintained in liquid form, together with vaporized fuel at the top ofthe reservoir,

erate said valve whereby as heat is extracted from the liquid fuel in the reservoir by vaporization in the reservoir due to the supply fuel to the x y heating burner, the valve is operated to give an increased gas supply to the reservoir yburner to thereby add heat for vaporization of the liquid fuel in the reservoir and hence increase the gas supplied to the heating burner and vice versa, the

means to automatically operate the valve com'-l prising a means responding to the vapor pressure in the reservoir whereby as thel vapor pressure decreases, the said valve is opened and vice versa, and a means including a thermostat exposed to the atmosphere approximate to the heating burner whereby as the atmospheric temperature decreases, the opening of the valve is increased, and vice versa.

6. An apparatus for preparing and using a fuel of the butane-propane type or series, comprising in combination a closed reservoir in which the fuel is maintained in liquid form together with vaporized. fuel, a heating burner exposed to the atmosphere for heating, a liquid connection from the reservoir to the burner, a reservoir burner for heating the reservoir, a liquid fuel connection means from the reservoir to said reservoir burner with a valve therein, the fuel being forced to the burnersby the vapor pressure in the reservoir and a means to automatically regulate said valve to increase the fuel supply to the reservoir burner in accordance with the liquid fuel required for the heating burner to maintain the desired atmospheric temperature whereby as the heat is extracted from the liquid in the reservoir by vapoxization of the fuel, the valve is opened to increase the ow of fuel to the reservoir burner and vice versa, the control means for the liquid fuel valve including a thermostat exposed to the atmosphere in proximity to the heating burner whereby decrease of the vatmospheric temperature operates to increase the opening of the valve and vice versa. p

'7. An apparatus for preparing and using a fuel of the butane-propane type or series, comprising in combination a closed reservoir in which the fuel is maintained in liquid form together with vaporized fuel, a heating burner exposed'to the atmosphere for heating, a liquid connection from the reservoir to the burner, a reservoir burner for heating the reservoir, a liquid fuel connection 'means from the reservoir to said reservoir burner and a means to automatically regulate said valve to increase the fuel supply to the reservoir burner v4in accordance with the liquid fuel required for the heating burner to maintain the desired atmospheric temperature whereby as the heat is extracted from the liquid in the reservoir by vaporization of the fuel, the valve is opened to increase the ow of fuel to the reservoir burner and vice versa, the control means for the liquid fuel valve including a thermostat exposed to the atmosphere in proximity tothe heating burner whereby decrease of the atmospheric temperature operates to increase the opening of the valve and vice Versa, and including a pressure responsive means connected to the top of the reservoir whereby changes of vapor pressure in the reservoir change the Valve opening, a decreasing vapor pressure increasing the valve opening and vice versa.

WILLIAM TscHUDY. THOMAS W. HALImAy. 

